Anti-cholinesterase drugs include the following drugs EXCEPT:

Correct Answer: B

Rationale: The correct answer is B: Carbachol. Anti-cholinesterase drugs inhibit the enzyme acetylcholinesterase, increasing levels of acetylcholine. Carbachol is a direct cholinergic agonist, not an anti-cholinesterase drug. Physostigmine, Metrifonate, and Neostigmine are all anti-cholinesterase drugs that work by inhibiting acetylcholinesterase. Physostigmine is used for glaucoma and atropine overdose, Metrifonate for parasitic infections, and Neostigmine for myasthenia gravis.

Correct Answer: D

Rationale: The correct answer is D: Propranolol. Propranolol is a beta-blocker that blocks the beta-adrenergic receptors in the heart, preventing the reflex increase in heart rate caused by nitroglycerin. This action helps to counteract the potentially dangerous side effect of increased heart rate. A: Atropine is not the correct answer because it is an anticholinergic drug that increases heart rate, which would exacerbate the reflex cardiac stimulation caused by nitroglycerin. B: Cocaine is a stimulant drug that can further increase heart rate and is not used to inhibit reflex cardiac stimulation. C: Phentolamine is an alpha-blocker that primarily acts on alpha-adrenergic receptors and is not the preferred drug for inhibiting the reflex increase in heart rate caused by nitroglycerin.

Correct Answer: C

Rationale: The correct answer is C: Reduced blood pressure, hypotension. Quinidine's strong postsynaptic alpha-adrenergic receptor blocking activity would result in decreased activation of these receptors, leading to vasodilation and reduced blood pressure, which can cause hypotension. Choice A is incorrect because lacrimal and mucus secretions are not directly affected by alpha-adrenergic receptor blocking. Choice B is incorrect as dilated pupils are more associated with alpha-1 adrenergic receptor blockade. Choice D is incorrect as skeletal muscle tremors are not a typical side effect of alpha-adrenergic receptor blocking.

Correct Answer: D

Rationale: The correct answer is D because biodiversity refers to the variety of living organisms in an ecosystem, specifically the number of different species present. This term encompasses all forms of life, from bacteria to plants to animals. Choice A is incorrect as it only focuses on the increase in the number of species, not the overall diversity. Choice B is incorrect as it describes the interaction between organisms and their environment, not the diversity of species. Choice C is incorrect as it limits biodiversity to only animals, neglecting the importance of other living organisms in an ecosystem.

Correct Answer: C

Rationale: When aqueous silver nitrate is added to a mixture, a yellow precipitate forms if there are chloride ions present. This is due to the formation of silver chloride, which is insoluble in water. The reaction is AgNO3 + Cl- → AgCl↓ + NO3-. Therefore, choice C is correct. Choice A (white precipitate) is incorrect because silver chloride is yellow, not white. Choice B (white solution) is incorrect as a precipitate forms, not a solution. Choice D (yellow solution) is incorrect because the product is a solid precipitate, not a solution.